Testing method and system suitable for synchronous motor static frequency conversion starting system

Abstract

The invention discloses a test method and system suitable for a static variable-frequency starting system of a synchronous motor, and relates to the technical field of synchronous motor testing, and the method comprises the steps: constructing the static variable-frequency starting system of the synchronous motor, carrying out an electrical primary circuit withstand voltage test, and carrying out initial system preparation after the test is completed; after initial system preparation is completed, synchronous motor rotor position detection and stator through-flow test are carried out; starting and grid-connected testing of the synchronous motor are carried out after the synchronous motor rotor test is completed, and the synchronous motor static frequency conversion starting system test is ended after the unit completes grid-connected operation. By constructing the complete static variable-frequency starting system, accurate control and efficient management of the starting process of the synchronous motor are realized, impact current in the starting process can be effectively reduced, the influence on a power grid is reduced, and the controllability and safety of the starting process are improved. The risk possibly occurring in the starting process is reduced, the synchronous motor can be stably connected to the power grid, and the impact on the power grid is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of synchronous motor testing, and in particular to a testing method and system suitable for a synchronous motor static variable frequency starting system. Background Art

[0002] With the continuous expansion of the scale of power systems and the increase in the proportion of renewable energy generation, synchronous motors such as pumped storage units, gas turbine units, and phase-converter units have become increasingly prominent as important flexibility resources. These synchronous motors can not only provide fast-response auxiliary services, but also effectively balance supply and demand fluctuations and improve the overall stability of the power grid. In order to achieve efficient startup of these units, the static frequency conversion starting system (SFC) has become one of the mainstream technologies. SFC controls the speed of the motor by changing the frequency input to the motor, thereby achieving a smooth startup process. In recent years, with the improvement of the performance of power electronic devices and the optimization of control strategies, the reliability and efficiency of SFC systems have been significantly improved. In particular, breakthroughs have been made in the miniaturization and high efficiency of power electronic devices, enabling SFC systems to operate at a wider range of voltage levels while maintaining low losses and high conversion efficiency. In addition, with the advancement of microprocessors and digital signal processing technology, the control accuracy and response speed of SFC systems have also been significantly improved, which helps to better adapt to changes in the power grid and improve the overall dynamic performance of the system.

[0003] Although SFC technology has made great progress, there are still deficiencies in some key links. First, due to the complexity and high degree of customization of the SFC system, its installation and commissioning cycle is long, which makes it difficult to meet the needs of rapid grid connection of power stations. Especially in new power stations or renovation projects, since the power station needs to complete the commissioning and grid connection testing of the equipment in a short time so that it can be put into operation as soon as possible to play its role in the power grid, higher requirements are placed on the installation and commissioning efficiency of the starting system. Secondly, during the startup process, SFC may generate large harmonic interference, affecting the power quality of the power grid. This harmonic interference will not only affect the normal operation of other electrical equipment, but may also cause problems such as grid oscillation. In addition, for large synchronous motors, the impact current and torque fluctuations during the startup process may have an adverse effect on the motor and its transmission device, and even shorten the service life of the equipment. Summary of the invention

[0004] In view of the problems existing in the existing testing methods applicable to the static variable frequency starting system of synchronous motors, the present invention is proposed. Therefore, the problem to be solved by the present invention is how to provide a testing method and system applicable to the static variable frequency starting system of synchronous motors.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a test method applicable to a static frequency conversion starting system of a synchronous motor, which includes constructing a static frequency conversion starting system of a synchronous motor, performing a withstand voltage test on the primary electrical circuit, and performing initial system preparation after the test is completed; after completing the initial system preparation, performing synchronous motor rotor position detection and stator current-carrying test; after completing the synchronous motor rotor test, performing the starting and grid connection test of the synchronous motor, and ending the test of the static frequency conversion starting system of the synchronous motor when the unit completes grid-connected operation.

[0007] As a preferred embodiment of the test method applicable to the static frequency conversion starting system of the synchronous motor according to the present invention, wherein: the static frequency conversion starting system of the synchronous motor includes a monitoring system, a static frequency conversion starting system, an excitation system, and a synchronization system.

[0008] As a preferred embodiment of the test method applicable to the static frequency conversion starting system of the synchronous motor according to the present invention, wherein: the performing of the initial system preparation includes the following steps. When the withstand voltage test of the primary electrical circuit is normal, perform a live test on the input transformer; the monitoring system executes the operation of closing the input circuit breaker, and the input transformer and the SFC system are in a live state; the SFC system measures the amplitude and phase sequence of the input voltage to determine whether the voltage amplitude and phase sequence meet the requirements of the starting system; obtain the allowable voltage amplitude range as [V min , V max , where V min is the minimum allowable voltage amplitude and V max is the maximum allowable voltage amplitude; if the input voltage amplitude V satisfies V min ≤V≤V max , then the voltage amplitude is qualified, perform voltage phase sequence judgment, and perform an excitation current-carrying test after the system voltage phase sequence judgment passes; if the input voltage amplitude V max <V or V<V min , then the voltage amplitude is unqualified, prompt that the input voltage is abnormal and re-check the input power supply, stop the starting system test, adjust the power supply voltage to the allowable range, and re-execute the live test on the input transformer.

[0009] As a preferred embodiment of the test method applicable to the static frequency conversion starting system of the synchronous motor according to the present invention, wherein: the performing of the excitation current-carrying test includes the following steps. Send an excitation start command and an excitation reference value to the excitation system through the SFC system, perform excitation system response determination. If the excitation system responds within the limited time, it is considered that the excitation system response is normal, perform excitation current deviation determination, obtain the excitation reference value and the actual given excitation current of the excitation system, and set the allowable maximum deviation percentage as ΔI max %; calculate the excitation current deviation percentage, and the calculation formula is:

[0010]

[0011] Where ΔI is the excitation current deviation percentage, I ref is the excitation reference value, I act is the actual excitation current given by the excitation system; if ΔI≤ΔI max %, it is determined that the excitation current deviation is within the allowable range, the excitation current test is passed, and the synchronous motor rotor position detection and stator current test are carried out.

[0012] As a preferred solution of the test method for the static variable frequency starting system of a synchronous motor described in the present invention, the synchronous motor rotor position detection and stator current flow test include the following steps: the SFC system performs a single-step operation on the main control device to control the unit rotor excitation current to determine the initial position of the rotor in a static state; obtains the excitation current step value, tests whether the excitation current reaches the excitation current step value, and if the excitation current does not reach the excitation current step value, it prompts that the excitation current does not reach the set value, checks the excitation system, stops the test of the static variable frequency starting system of the synchronous motor, performs self-diagnosis of the excitation system, and re-executes the rotor position detection test; if the excitation current reaches the excitation current step value, then continues to calculate the average value of the instantaneous value of the computer terminal voltage to determine whether the unit terminal voltage change exceeds the limited change range; if the unit terminal voltage change does not exceed the limited change range, the rotor position cannot be detected, and the terminal voltage is rechecked. Detection circuit, re-execute the rotor position detection test; if the unit terminal voltage change exceeds the specified range, the unit rotor position change is detected, the real-time rotor position is recorded, and the stator current test is continued; based on the detected initial position of the rotor, two-phase windings are selected on the stator for current flow to obtain the maximum initial torque, so that the rotor can get rid of the initial position and achieve a small angle rotation; if the initial torque of the stator is less than the minimum initial torque, it is judged that the initial torque is insufficient, the stator current is checked, the unit start-up test is stopped to check the stator winding current, and the stator current test is re-executed; if the initial torque of the stator is above the minimum initial torque, the initial torque is sufficient, the initial torque value is recorded, and the test is continued to determine the rotor angular velocity change. If the rotor angular velocity change meets the test requirements, the rotor angular velocity change value is recorded, the synchronous motor rotor position detection and stator current test are completed, and the synchronous motor is started and connected to the grid.

[0013] As a preferred solution of the test method for the static frequency conversion starting system of a synchronous motor described in the present invention, the starting and grid-connected test of the synchronous motor includes the following steps: setting the target speed on the SFC system main control device, the monitoring system issues a start command, and the SFC system starts the unit according to a predetermined procedure until the target speed is reached; the monitoring system issues a stop command to make the unit start to enter the idling state, and obtain the target speed and the speed deviation threshold; if the speed deviation is greater than the speed deviation threshold, it is determined that the speed has not reached the target value, the SFC system is rechecked, the static frequency conversion starting test of the synchronous motor is stopped, the SFC system parameters are adjusted to re-execute the fixed speed starting test; if the speed deviation is below the speed deviation threshold, it is determined that the unit speed has reached the target speed, the static frequency conversion starting speed test of the synchronous motor has passed, the time when the speed reaches the target speed is recorded, and the test continues. Perform false synchronization test; when the synchronization device detects that the state of the unit meets the grid-connected conditions, the grid-connected switch in the test position is closed. After the SFC system receives the synchronization closing order or detects that the grid-connected switch is in the closed position, it starts to seal the pulse and open the switch to put the unit into the idling state; determine whether the grid-connected conditions meet the grid-connected requirements of the unit. If the synchronization device meets the grid-connected conditions, the time when the grid-connected conditions are met is recorded, and the true synchronization test of the unit is continued; when the synchronization device detects that the state of the unit meets the grid-connected conditions, the grid-connected switch in the working position is closed. After the SFC system receives the synchronization closing order or detects that the grid-connected switch is in the closed position, it starts to seal the pulse and open the switch, and the unit is connected to the grid to monitor the operating status of the unit after being connected to the grid; if the operating status of the unit after being connected to the grid meets the set conditions of the unit, the synchronous motor static frequency conversion starting system test is ended, and the synchronous motor static frequency conversion starting system test optimization is performed.

[0014] As a preferred solution of the test method for the static variable frequency starting system of a synchronous motor described in the present invention, the test optimization of the static variable frequency starting system of the synchronous motor includes the following steps: using a data acquisition device to record all test data during the test and exporting them to a database for sorting, performing statistical analysis on the data, identifying performance bottlenecks during the start-up test, and evaluating the stability during the grid connection process; adjusting system parameters according to the data analysis results, and recalibrating the system limit judgment value; checking the static variable frequency starting system of the synchronous motor, formulating a preventive maintenance schedule, and adjusting the system parameters and then retesting to verify the optimization effect.

[0015] In the second aspect, the present invention provides a test system suitable for a static variable frequency starting system of a synchronous motor, comprising: a construction module, used to construct a static variable frequency starting system of a synchronous motor, perform an electrical primary circuit withstand voltage test, and perform initial system preparation after the test is completed; a preparation module, used to perform a synchronous motor rotor position detection and a stator current flow test after completing the initial system preparation; a test module, used to perform a start-up and grid-connected test of the synchronous motor after completing the synchronous motor rotor test, and end the static variable frequency starting system test of the synchronous motor after the unit completes the grid-connected operation.

[0016] In a third aspect, the present invention provides a computer device including a memory and a processor, wherein the memory stores a computer program, wherein: when the processor executes the computer program, the steps of a test method applicable to a static variable frequency starting system of a synchronous motor are implemented.

[0017] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, the steps of a test method applicable to a static variable frequency starting system of a synchronous motor are implemented.

[0018] The beneficial effects of the present invention are that by constructing a complete static variable frequency starting system, the precise control and efficient management of the synchronous motor starting process can be achieved, the impact current during the starting process can be effectively reduced, the impact on the power grid can be reduced, and the controllability and safety of the starting process can be improved. The risks that may occur during the starting process can be reduced, so that the synchronous motor can be smoothly connected to the power grid and the impact on the power grid can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 The present invention is a flow chart of a test method applicable to a static variable frequency starting system of a synchronous motor.

[0021] Figure 2 It is a structural topology diagram suitable for the static variable frequency starting system of synchronous motor. DETAILED DESCRIPTION

[0022] In order to make the above-mentioned purposes, features and advantages of the present invention more understandable, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0023] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0024] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0025] Example 1

[0026] Reference Figure 1 , which is the first embodiment of the present invention, provides a test method for a synchronous motor static variable frequency starting system, comprising:

[0027] S1: Build a synchronous motor static variable frequency starting system, conduct a withstand voltage test on the electrical primary circuit, and perform initial system preparation after the test is completed;

[0028] Specifically, the static variable frequency starting system of synchronous motor includes monitoring system, static variable frequency starting system, excitation system and synchronization system. Synchronous motor is mainly used in the fields of pumped storage, gas turbine, phase regulator, etc.

[0029] When the electrical primary circuit withstand voltage test is normal, the input transformer is energized for testing; the monitoring system closes the input circuit breaker, and the input transformer and SFC system are energized;

[0030] The SFC system measures the input voltage amplitude and phase sequence to determine whether the voltage amplitude and phase sequence meet the requirements of the startup system;

[0031] The allowable range of voltage amplitude is [V min ,V max ], where V min is the minimum allowable voltage amplitude, V max is the maximum allowable voltage amplitude;

[0032] If the input voltage amplitude V satisfies Vmin V ≤ V ≤ V max If so, the voltage amplitude is qualified, and the voltage phase sequence is judged;

[0033] If the input voltage amplitude V max < V or V < V min If so, the voltage amplitude is unqualified. Prompt to recheck the input power supply for abnormal input voltage, stop the startup system test, adjust the power supply voltage to the allowable range, and re - execute the live test of the input transformer.

[0034] Send an excitation start command and an excitation reference value to the excitation system through the SFC system, and judge the response of the excitation system. If the excitation system responds within the limited time, it is considered that the excitation system responds normally, and the excitation current deviation is judged. Obtain the excitation reference value and the actual given excitation current of the excitation system, and set the allowable maximum deviation percentage as ΔI max %;

[0035] Calculate the excitation current deviation percentage. The calculation formula is:

[0036]

[0037] In the formula, ΔI is the excitation current deviation percentage, I ref is the excitation reference value, and I act is the actual given excitation current of the excitation system;

[0038] If ΔI ≤ ΔI max %, it is determined that the excitation current deviation is within the allowable range, the excitation current - passing test passes, and the rotor position detection of the synchronous motor and the stator current - passing test are carried out.

[0039] S2: After completing the initial system preparation, carry out the rotor position detection of the synchronous motor and the stator current - passing test;

[0040] Specifically, for the rotor position detection test: The SFC system performs single - step operations on the main control device, including steps such as unit selection, starting cooling, closing the output breaker, closing the input breaker, and starting excitation. The SFC system controls the excitation, gives a step - type excitation current to the rotor of the unit, and determines the initial position of the rotor in the stationary state by detecting the instantaneous value of the terminal voltage.

[0041] The SFC system performs single - step operations on the main control device, including steps such as unit selection, starting cooling, closing the output breaker, closing the input breaker, and starting excitation. The SFC system controls the excitation current of the unit rotor and determines the initial position of the rotor in the stationary state by detecting the instantaneous value of the terminal voltage;

[0042] Get the excitation current step value, test whether the excitation current reaches the excitation current step value. If the excitation current does not reach the excitation current step value, it will prompt that the excitation current has not reached the set value. Check the excitation system, stop the synchronous motor static variable frequency starting system test, perform excitation system self-diagnosis, and re-execute the rotor position detection test;

[0043] If the excitation current reaches the excitation current step value, the average value of the instantaneous value of the terminal voltage is continued to be calculated to determine whether the unit terminal voltage change exceeds the limited change range;

[0044] If the unit terminal voltage change does not exceed the limited change range, the rotor position cannot be detected. Recheck the unit terminal voltage detection circuit and re-perform the rotor position detection test;

[0045] If the unit terminal voltage changes beyond the specified range, the unit rotor position is detected to have changed, the real-time rotor position is recorded, and the stator current flow test is continued;

[0046] Stator current flow test: Based on the detected initial position of the rotor, the SFC system performs single-step operations on the main control device, including unit selection, start cooling, close output circuit breaker, close input circuit breaker, start excitation and pulse unlocking. According to the position of the rotor, the corresponding two-phase winding is selected on the stator for current flow to obtain the maximum initial torque, so that the rotor can get rid of the initial position and achieve a small angle rotation.

[0047] Based on the detected initial position of the rotor, two-phase windings are selected on the stator for current flow to obtain the maximum initial torque, so that the rotor can get rid of the initial position and achieve a small angle rotation;

[0048] If the initial torque of the stator is less than the minimum initial torque, it is judged that the initial torque is insufficient, and the stator current is checked. The unit is stopped for startup test to check the stator winding current, and the stator current test is performed again.

[0049] If the initial torque of the stator is above the minimum initial torque, the initial torque is sufficient. The initial torque value is recorded, and the test is continued to determine the change in the rotor angular velocity. If the change in the rotor angular velocity meets the test requirements, the rotor angular velocity change value is recorded, the synchronous motor rotor position detection and stator current flow test are completed, and the synchronous motor is started and connected to the grid for testing.

[0050] S3: After completing the synchronous motor rotor test, the synchronous motor start-up and grid-connection test are carried out. When the unit completes the grid-connection operation, the synchronous motor static frequency conversion starting system test is terminated.

[0051] Specifically, the fixed speed start test: after the target speed is set on the SFC system main control device, the monitoring system issues a start command, and the SFC system starts the unit according to the predetermined procedure until the target speed is reached. Then the monitoring system issues a stop command to make the unit start idling.

[0052] The target speed is set on the SFC system main control device, the monitoring system issues a start command, and the SFC system starts the unit according to the predetermined procedure until the target speed is reached;

[0053] The monitoring system issues a shutdown command to put the unit into an idling state and obtains the target speed and speed deviation threshold;

[0054] If the speed deviation is greater than the speed deviation threshold, it is determined that the speed has not reached the target value, and the SFC system is rechecked, the synchronous motor static variable frequency starting test is stopped, and the SFC system parameters are adjusted to re-execute the fixed speed starting test;

[0055] If the speed deviation is below the speed deviation threshold, it is determined that the unit speed has reached the target speed, the synchronous motor static variable frequency starting speed test has passed, the time when the speed reaches the target speed is recorded, and the false synchronization test is continued;

[0056] False synchronization test: When the synchronization device detects that the unit status meets the grid connection conditions, the grid connection switch in the test position is closed. After the SFC system receives the "synchronous closing command" or detects that the grid connection switch is in the closed position, it starts to seal the pulse and open the switch to put the unit into the idling state.

[0057] When the synchronization device detects that the unit status meets the grid connection conditions, the grid connection switch in the test position is closed. After the SFC system receives the synchronization closing command or detects that the grid connection switch is in the closed position, it starts to seal the pulse and open the switch to put the unit into the idling state;

[0058] Determine whether the grid-connected conditions meet the grid-connected requirements of the unit. If the synchronization device meets the grid-connected conditions, record the time when the grid-connected conditions are met and continue the true synchronization test of the unit;

[0059] True synchronization test: When the synchronization device detects that the unit status meets the grid connection conditions, the grid connection switch in the working position is closed. After the SFC system receives the "synchronous closing command" or detects that the grid connection switch is in the closed position, it starts to seal the pulse and open the switch to enable the unit to achieve true grid connection operation.

[0060] When the synchronization device detects that the status of the unit meets the grid-connected conditions, the grid-connected switch in the working position is closed. After the SFC system receives the synchronization closing command or detects that the grid-connected switch is in the closed position, it starts to seal the pulse and open the switch. The unit is connected to the grid and the operating status of the unit after grid connection is monitored. The static frequency conversion starting system of the synchronous motor is tested and optimized.

[0061] If the running status of the unit after being connected to the grid meets the set conditions of the unit, the test of the synchronous motor static frequency conversion starting system is terminated.

[0062] Use data acquisition equipment to record all test data during the test and export them to the database for sorting, perform statistical analysis on the data, identify performance bottlenecks during the startup test, and evaluate stability during the grid connection process;

[0063] Adjust system parameters according to data analysis results, such as excitation current setting value, excitation curve, etc. Adjust SFC system parameters, such as current ramp and frequency control in the startup procedure. Adjust synchronous system parameters, such as synchronous voltage deviation threshold, frequency deviation threshold, etc. And recalibrate system limit judgment value;

[0064] Check the synchronous motor static variable frequency starting system, formulate a preventive maintenance schedule, adjust system parameters and retest to verify the optimization effect.

[0065] Furthermore, the present embodiment also provides a test system suitable for a static variable frequency starting system of a synchronous motor, comprising: a construction module, used to construct a static variable frequency starting system of a synchronous motor, perform an electrical primary circuit withstand voltage test, and perform initial system preparation after the test is completed; a preparation module, used to perform a synchronous motor rotor position detection and a stator current flow test after completing the initial system preparation; a test module, used to perform a start-up and grid-connected test of the synchronous motor after completing the synchronous motor rotor test, and terminate the static variable frequency starting system test of the synchronous motor after the unit completes the grid-connected operation.

[0066] This embodiment also provides a computer device, which is suitable for the testing method of the static frequency conversion starting system of a synchronous motor, including: a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute computer executable instructions to implement all or part of the steps of the method described in the embodiment of the present invention as proposed in the above embodiment.

[0067] This embodiment also provides a storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the method in any optional implementation of the above embodiment is executed. Wherein, the storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (Static Random Access Memory, referred to as SRAM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read Only Memory, referred to as EEPROM), erasable programmable read-only memory (Erasable Programmable Read Only Memory, referred to as EPROM), programmable read-only memory (Programmable Red Only Memory, referred to as PROM), read-only memory (Read Only Memory, referred to as ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0068] The storage medium proposed in this embodiment and the data storage method proposed in the above embodiment belong to the same inventive concept. The technical details not fully described in this embodiment can be found in the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0069] As can be seen from the above, this method realizes precise control and efficient management of the synchronous motor starting process by constructing a complete static variable frequency starting system, providing a solid foundation for subsequent testing. It can effectively reduce the impact current during the starting process, reduce the impact on the power grid, and improve the controllability and safety of the starting process. Ensure the stable operation of the system during the starting process, and the electrical connection problems found during the test can be corrected in time to avoid starting failure or equipment damage caused by electrical failure. Improve the overall safety of the system and reduce the risks that may occur during the starting process. Ensure the safety of the starting process. Reduce starting failures or other electrical problems caused by mismatched input power. Can verify the working status of the excitation system, ensure that the excitation current can be given in the expected manner, and improve the controllability and stability of the dynamic process. Enable the synchronous motor to be smoothly connected to the power grid and reduce the impact on the power grid.

[0070] Example 2

[0071] Referring to Table 1, which is a second embodiment of the present invention, this embodiment provides a test method suitable for a static variable frequency starting system of a synchronous motor. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0072] Table 1 Technical characteristics comparison table

[0073]

[0074] As can be seen from the above, this method realizes precise control and efficient management of the synchronous motor starting process by constructing a complete static variable frequency starting system, providing a solid foundation for subsequent testing. It can effectively reduce the impact current during the starting process, reduce the impact on the power grid, and improve the controllability and safety of the starting process. Ensure the stable operation of the system during the starting process, and the electrical connection problems found during the test can be corrected in time to avoid starting failure or equipment damage caused by electrical failure. Improve the overall safety of the system and reduce the risks that may occur during the starting process. Ensure the safety of the starting process. Reduce starting failures or other electrical problems caused by mismatched input power. Can verify the working status of the excitation system, ensure that the excitation current can be given in the expected manner, and improve the controllability and stability of the dynamic process. Enable the synchronous motor to be smoothly connected to the power grid and reduce the impact on the power grid.

[0075] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A test method for a synchronous motor static variable frequency starting system, characterized in that: include, Build a synchronous motor static variable frequency starting system, conduct a withstand voltage test on the electrical primary circuit, and perform initial system preparation after the test is completed; After completing the initial system preparation, perform synchronous motor rotor position detection and stator current flow test; After completing the synchronous motor rotor test, the synchronous motor start-up and grid-connection test are carried out. When the unit completes the grid-connected operation, the synchronous motor static frequency conversion starting system test is terminated.

2. The testing method for a synchronous motor static variable frequency starting system as claimed in claim 1, characterized in that: The synchronous motor static frequency conversion starting system comprises a monitoring system, a static frequency conversion starting system, an excitation system and a synchronization system.

3. The testing method for a synchronous motor static variable frequency starting system as claimed in claim 2, characterized in that: The initial system preparation comprises the following steps: When the electrical primary circuit withstand voltage test is normal, conduct a live test on the input transformer; The monitoring system closes the input circuit breaker, and the input transformer and SFC system are energized; The SFC system measures the input voltage amplitude and phase sequence to determine whether the voltage amplitude and phase sequence meet the requirements of the startup system; The allowable range of voltage amplitude is [V min ,V max ], where V min is the minimum allowable voltage amplitude, V max is the maximum allowable voltage amplitude; If the input voltage amplitude V satisfies V min ≤V≤V max When the voltage amplitude is qualified, the voltage phase sequence is judged, and the excitation current test is carried out after the system voltage phase sequence is judged to be passed; If the input voltage amplitude V max < V or V < V min , the voltage amplitude is unqualified. Prompt to check the input power supply again for abnormal input voltage, stop the startup system test, adjust the power supply voltage to the allowable range, and re - execute the live test of the input transformer.

4. The testing method for a synchronous motor static variable frequency starting system as claimed in claim 3, characterized in that: The excitation flux test comprises the following steps: The excitation start command and excitation reference value are sent to the excitation system through the SFC system to determine the response of the excitation system. If the excitation system responds within the time limit, it is considered that the excitation system responds normally. The excitation current deviation is determined to obtain the excitation reference value and the excitation current actually given by the excitation system. The maximum allowable deviation percentage is set to ΔI. max %; Calculate the excitation current deviation percentage, the calculation formula is: Where ΔI is the excitation current deviation percentage, I ref is the excitation reference value, I act is the actual given excitation current of the excitation system; If ΔI≤ΔI max %, it is determined that the excitation current deviation is within the allowable range, the excitation current test is passed, and the synchronous motor rotor position detection and stator current test are carried out.

5. The testing method for a synchronous motor static variable frequency starting system as claimed in claim 4, characterized in that: The synchronous motor rotor position detection and stator current flow test comprises the following steps: The SFC system performs single-step operation on the main control device to control the unit rotor excitation current to determine the initial position of the rotor in the static state; Get the excitation current step value, test whether the excitation current reaches the excitation current step value. If the excitation current does not reach the excitation current step value, it will prompt that the excitation current has not reached the set value. Check the excitation system, stop the synchronous motor static variable frequency starting system test, perform excitation system self-diagnosis, and re-execute the rotor position detection test; If the excitation current reaches the excitation current step value, the average value of the instantaneous value of the terminal voltage is continued to be calculated to determine whether the unit terminal voltage change exceeds the limited change range; If the unit terminal voltage change does not exceed the limited change range, the rotor position cannot be detected. Recheck the unit terminal voltage detection circuit and re-perform the rotor position detection test; If the unit terminal voltage changes beyond the specified range, the unit rotor position is detected to have changed, the real-time rotor position is recorded, and the stator current flow test continues; Based on the detected initial position of the rotor, two-phase windings are selected on the stator for current flow to obtain the maximum initial torque, so that the rotor can get rid of the initial position and achieve a small angle rotation; If the initial torque of the stator is less than the minimum initial torque, it is judged that the initial torque is insufficient, and the stator current is checked. The unit is stopped for startup test to check the stator winding current, and the stator current test is performed again. If the initial torque of the stator is above the minimum initial torque, the initial torque is sufficient. The initial torque value is recorded, and the test is continued to determine the change in the rotor angular velocity. If the change in the rotor angular velocity meets the test requirements, the rotor angular velocity change value is recorded, the synchronous motor rotor position detection and stator current flow test are completed, and the synchronous motor is started and connected to the grid for testing.

6. The testing method for a synchronous motor static variable frequency starting system as claimed in claim 5, characterized in that: The starting and grid-connection test of the synchronous motor includes the following steps: The target speed is set on the SFC system main control device, the monitoring system issues a start command, and the SFC system starts the unit according to the predetermined procedure until the target speed is reached; The monitoring system issues a shutdown command to put the unit into an idling state and obtains the target speed and speed deviation threshold; If the speed deviation is greater than the speed deviation threshold, it is determined that the speed has not reached the target value, and the SFC system is rechecked, the synchronous motor static variable frequency starting test is stopped, and the SFC system parameters are adjusted to re-execute the fixed speed starting test; If the speed deviation is below the speed deviation threshold, it is determined that the unit speed has reached the target speed, the synchronous motor static variable frequency starting speed test has passed, the time when the speed reaches the target speed is recorded, and the false synchronization test is continued; When the synchronization device detects that the unit status meets the grid connection conditions, the grid connection switch in the test position is closed. After the SFC system receives the synchronization closing command or detects that the grid connection switch is in the closed position, it starts to seal the pulse and open the switch to put the unit into the idling state; Determine whether the grid-connected conditions meet the grid-connected requirements of the unit. If the synchronization device meets the grid-connected conditions, record the time when the grid-connected conditions are met and continue the true synchronization test of the unit; When the synchronization device detects that the status of the unit meets the grid-connected conditions, the grid-connected switch in the working position is closed. After the SFC system receives the synchronization closing command or detects that the grid-connected switch is in the closed position, it starts to seal the pulse and open the switch. The unit is connected to the grid and the operating status of the unit after the grid connection is monitored; If the running status of the unit after being connected to the grid meets the set conditions of the unit, the test of the synchronous motor static variable frequency starting system is terminated, and the test optimization of the synchronous motor static variable frequency starting system is performed.

7. The testing method for a synchronous motor static variable frequency starting system as claimed in claim 6, characterized in that: The test optimization of the synchronous motor static variable frequency starting system includes the following steps: Use data acquisition equipment to record all test data during the test and export them to the database for sorting, perform statistical analysis on the data, identify performance bottlenecks during the startup test, and evaluate stability during the grid connection process; Adjust system parameters based on data analysis results and recalibrate system limit judgment values; Check the synchronous motor static variable frequency starting system, formulate a preventive maintenance schedule, adjust system parameters and retest to verify the optimization effect.

8. A test system for a synchronous motor static variable frequency starting system, based on the test method for a synchronous motor static variable frequency starting system according to any one of claims 1 to 7, characterized in that: include, Construction module, used to build a synchronous motor static variable frequency starting system, conduct electrical primary circuit withstand voltage test, and perform initial system preparation after the test is completed; A preparation module, used to perform synchronous motor rotor position detection and stator current flow test after completing the initial system preparation; The test module is used to complete the synchronous motor rotor test and then perform the synchronous motor start-up and grid-connection test. When the unit completes the grid-connection operation, the synchronous motor static variable frequency starting system test ends.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the test method applicable to the static variable frequency starting system of a synchronous motor according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the test method applicable to a static variable frequency starting system of a synchronous motor as claimed in any one of claims 1 to 7 are implemented.

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